Internal-combustion engine.



o. LAS'CHE. INTERNAL COMBUSTION ENGINE.

VAPPLICATION FILED JULYS, 1914.

Patented Deo.

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Witnesses escape through the inlet ports UNITED sTATEs PATENT oEErcE.

OSKAB LASCHE, 0F CHARLOTTENBURG, GERMANY, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

INTERNAL-GOMBUSTION ENGINE.

neonato.

To alt ywhom t may concern.' Be it known that I, OSKAR LAscHE, a sub- `iect of the Emperor of Germany, residing at Charlottenburg, Germany, have invented certain new and useful mprovements in Internal-Combustion Engines, of ywhich the following is a specification.

The present invention relates to internal combustion engines of thetype having two oppositely moving pistons which Serve to cover and uncover the inlet or scavenging and exhaust ports, and in which the cranks of the respective pistons are angularly displaced relative to each other by an amount somewhat less than 180 degrees so that the piston which controls the exhaust ports.

lea ds the other. As is known, the advantage of this arrangement is that the exhaust ports are opened prior to the opening of the inletports so as to permit a portion of the'exhaust gases to escape and the pressure in the cylinder to decrease before the inlet ports are uncovered, and are closed prior to the closing of the inlet. ports so as to in crease the charge,

An engine of this type is designed to operate in one direction only, it being obvious that if reversed the piston `controlling the inlet ports would then lead that controlling the exhaust ports which would result in the inlet ports opening prior to the exhaust ports so that exhaust gases would y and mix with the incoming charge of air. This is due to the fact that the pressure in the cylinder at this time would be greater than that of the scavenging air.

The object of the present invention is to provide an arrangement whereby an engine f this type may be reversed.

F or a' consideration of what I believe to be novel and my invention, attention is directed to thev following specification and the claims appended thereto.

Referring to the drawing, Figure 1 is a longitudinal section of an internal combustion engine illustrating one form which my invention may take, and Fig. 2 is a similar View of a modification. '-i

ln carrying out my invention, provide suitable valve mcanscontrolling an auxiliary exhaust `passage from they cylinder which, when the engine is reversed, is arranged to be'opened prior to the uncoveringzoftbe inlet parts. By this means the Specification of Letters Patent.

Patented Dec. 5, 1916.

Application led July 8, 1914. Serial No. 849,685.

pressure in the cylinder is relieved before the inlet ports open when the engine is operated in a reverse direction. The valve means controlling the auxiliary exhaust may take various forms and be controlled in any suitable manner, although I prefer to control the same from a cam located on a cam shaft driven by the engine. v

Referring to Fig. 1, .3 indicates the cylinder and 4:, 5 the oppositely moving pistons which control the inlet or scavenging ports 6 and the exhaust ports 7. 8 indicates the receiver or conduit through which the scavenging air is led to the inlet ports. This air is supplied under pressure as is well understood. The exhaust gases are con-v lforward operation, which in the present instance is clockwise, the piston 5 leads the piston 4 for the reasons already referred to. Located in advance of the exhaust ports 7 is a second port or set of ports 14 which connect the cylinder by way of passage 15 to the exhaustl conduit 9 and are idle during forward running of the engine. Communication between passage 15 and the exhaust conduit is controlled by the valve 16 yieldingly held on its seat by the spring 17. The stem of 4this valve-is extended down to a point adjacent the cam shaft where it is connected by link 18 to one end of alever 19. The lever 19 is pivoted at its other end to the eccentric 20 by means of the eccentric strap 21. 22 is a handle for turning the eccentric. Carried by the lever-19 intermediate between its ends is a roller 23 which cooperates with the cam 211 to open and close the valve 16. By shifting the handle 22 to turn the eccentric the roller 23 can be moved into and out of position to be engaged by the operating cam 24. 25 indicates the opening through which fuel is introduced, the fuel injector itself being omitted.

During normal forward operation the eccentric 20 will be turned to the dotted line position, in which position the roller 23 will not be engaged by cam 24C and the valve 16 will remain closed. The engine will then operate in a forward direction in the ordi nary manner. When it is desired to reverse the engine, the handle 22 is moved to Y the full line position bringing the roller 23 into position to be engaged by cam 24, as show n in full lines. (ln reversal this cani will be turning in an anti-clockwise direction as indicated by the arrow and as shown will operate to open the valve 1G to connect the auxiliary exhaust ports 14 with the exhaust conduit prior to the time that the piston 4- uncovers the inlet or scavenging ports (S. 'l`he cam is so timed or positioiied as to open the valve at about the saine time that the piston 5 begins to uncover the ports 14 and to keep the same open at least until the ports 7 begin to uncover. By this arrangement it is insured tnat the pressure of the exhaust gases in the cylinder will be reduced below that of the air before the inlet ports are uncovered.

In Fig. 2 an arrangement is shown wherein the auxiliary exhaust is combined with the air starting valve, which arrangement has the advantage that no additional openings are then required through the cylinder wall. The engine illustrated in Fig. 2 is of the saine type as that illustrated in Fig. 1, and similar reference numerals have been applied to corresponding parts. In this figure, 30 indicates the auxiliary exhaust port, which is also the port through which the starting air is introduced. Controlling this port is a suitable valve mechanism so arranged that the saine may be operated to connect the` port either to exhaust or to the supply ot' starting air; in the present instance the mechanism is so arranged as to be connected to one or the other depending upon the degree oi actuation` but it will be iu'iderstood other arrangements may be used. To this end the port is controlled by the valve 81 yieldingly held on its seat byspring arranged between the outer wall of the valve casing 33 and the slide valve 34 carried by the valve stein 35. valve 31 is seated or only partially open, the slide valve 34 covers the opening 36 through which high pressure starting air is admitted from the pipe 3T. When fully unseated the slide valve uncovers opening' 8G and covers the opening 23S which is connected to the exhaust conduit by pipe 39. The slide valve is provided with an opening or series of openings 40 therethrough, as shown in dotted lines, and through which exhaust gases pass to the conduit S).

The end of theI valve stein 35 is connected to one arm of a hell crank, lever 41 pivoted at 42. rI`hc other arm of this lever is conneeted to one end ot the rod 43, the other end being connected to one end of the lever arm 4-1 through the link 45. At 46 is a second spring which assists the spring 32l .in holding the valve 3l in closed position.

The other eiid of the lever arm 44 is pivoted to the ecceiric i7 by means of the eccenlVhen the the carin In normal forward operation the handle 51 is moved to a horizontal position as shown in dotted lines. In this position the roller 49 is moved out of the p'ath of the cam 50. The valve 31 then remains seated and the engine operates in the ordinarl way, the direction of rotation of the cran shaft being clockwise. lVhen it is desired to reverse the engine the handle 51 is moved to the full line position. This brings the roller 49 into such position with 'relation to the cam that upon each revolution, the valve 31' will be partially opened, the extent of the opening being as indicated in the drawing where the parts are shown in the position they occupy just prior to the uncovering of the inlet ports by the piston 4. lVhen in this position the contents of the cylinder may escape through port or opening 30, passages 40, passage 38, and pipe 39 to the exhaust conduit 9, thus relieving the pressure in the cylinder prior to the uncoveriiig of the inlet or scavenging ports 6. On reversal the direction of rotation is anticlockwise as indicated by the arrow.

When it is desired to use the valve for starting purposes the handle 51 is turned to the vertical position as indicated in dotted lilies. This brings the roller 49 into such position with relation to the cam as to cause the cam upon each revolution to fully open the valve 31. The'slide valve 34 then uncovers the opening 36 and closes the port or opening 38. The starting air is thus admitted to start the engine in the usual manner.

In connection with each of the arrangements shown, it is to be noted that in each instance the exhaust gases from the auxiliary exhaust pass to the regular exhaust conduit so that only one exhaust pipe and niuiiler is required.

I have omitted specific reference to the means for introducing fuel into the combustion space in the cylinder between the pistons because it is unnecessary to an understanding of my invention, and it is to be understood that any suitable means ma)y be provided i'or the purpose.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof;

butI desire to have it understood that the y What I claim yas new and desire to secure by Letters Patent of the United States, is,-

1. In an internal combustion engine, the combination of a cylinder, oppositely moving pistons therein, inlet and exhaust ports which are covered and uncovered by the pistons, c anks for the pistons which are angularly lisplaced relative to each other by an angle other than 180O whereby upon forward operation the piston controlling the exhaust,

port leads the piston controlling the inlet portand means for relieving the pressure in the cylinder prior to the opening of the inlet port when the engine is reversed.

2. In an internal combustion engine, the

combination of a cylinder, oppositely moving pistons therein, inlet and exhaust ports which are covered and uncovered by the pistons, cranks for the pistons which are angulai-ly displaced relative to each other by an angle other than 180O whereby upon forward operation the piston controlling the exhaust- `ports lead the vpiston controlling the inlet port, an auxiliary exhaust port, a valve controlling the same, and means for opening said valve prior to the uncovering of the inlet pdr-t when theiengine is reversed.

3. In an internal combustion engine, the combination of a cylinder, oppositely lmoving pistons therein, inlet and exhaust ports which are covered and uncovered by the pistons, cranks for the pistons which are a ngularly displaced relative to each other by an angle other than 180 whereby upon frward operation the piston controlling the exhaustport leads the piston controlling the inlet port, an auxiliary exhaust port, an exhaust conduit, a conduit connecting the auxiliary exhaust port. with the exhaust con- Va valve controlling the same, a lever through which the valve is operated, an operating cam, and means for moving the lever into and out of operative position with relation to thecam.

In an internal combustion engine, the combination of a cylinder, oppositely moving pistons therein, inlet and exhaust ports which are covered and uncovered by the pistons, cranks for the pistons which are angularly displaced relative to each other by an angle other than i800 whereby upon forward operation the piston controlling the exhaustl ports leads the piston controlling the inlet ports, and a combined air starting and auxiliary exhaust valve mechanism therefor comprising a port-in the cylinder, a valve casing, a valve therein for the port, said casing having an exhaust opening and an opening for admitting starting air, and means for connecting the port to the exhaust opening' when the valve is opened to a certain extent and for connecting it to the opening for admitting starting air when opened to a different extent.

6. In an internal combustion engine, the combination of a. cylinder, oppositely moving pistons therein, inlet and exhaust ports which are covered and `uncovered byv the pistons, cranks for. the pistons whichmfare angularly displaced relative to each other by an angle other than 1800 whereby uponv forward operation the piston controlling .the exhaust ports leads the piston controlling the inlet ports, and a combined air starting and auxiliary exhaust valve l mechanism therefor comprising a port in the 4cylinder located in advance of the exhaust ports, a

valve casing, a'valve.Y therein for the port,

said casing having an exhaust opening and an open-ingv for admitting starting air, and a. second valve operating in connection with the first. vnamed valve for controlling the openings whereby theil port .may be connected with either of them.

7. In an internal combustion engine, .the

lcombination of a cylinder, 'oppositoly mov; ing pistons therein, inlet and exhaust ports which are covered and uncovered 'by theE pistons, cranks for the pistons which are angularly displaced relative to each other4 by an angle other than 180 whereby upon another position it opens the valve .and connects `theport to the opening for admits ting. starting air.

8. In an yinternal combustion engine, A

the combination of a cylinder, Aoppositely moving pistons therein, inlet and exhaust ports which are covered anduncovered by the pistons, 4cranks forthe pistons which are angularly displaced relative to each. other by .an angle other than' 18()o whereby upon forward operation `the piston conwhich are covered and uncovered by the pistons, cranks for the pistons which are angularly displaced relative to each other by an angle other than whereby upon forward operation Athe piston controlling the exhaust, por'ts leads the piston controlling the inlet ports, and a combined air starting and auxiliary exhaust valvel mechanism therefor comprising a port in the cylinder, a valve casing, a valve therein for the port, said casing having an exhaust opening and an opening for admitting-starting alr, means for connectirig the port to the exhaust opening or to the opening for admitting start-v ing airv according to the degree of actuation of the valve, a member through which the valve mechanism and the means are operated, a cam, and means for moving the member to different positions relative to the 'cam to vary the de of actuation.

10. In an interna combustion engine, the combinationl of a cylinder structure havinga combustion space, two pistons therein which move in unison toward and away from said combustion space, inlet and exhaust ports which are covered and uncovered by the pistons, cranks for the pistons which are angularly displaced relative to each other b an angle other than 180 whereby upon orward operation the piston controllin the exhaust port leads the piston contro ling the inlet port, and an auxiliary exhaust port that is opened to relieve the pressure in the cylinder priorto the openlng of the inlet port when the engine is reversed.

11. In an internal combustion engine, the combination of a cylinder structure having a combustion space, two pistons therein which move in unisonptoward and away from said combustion space, inlet and exhaust ports which are covered and uncovered by the pistons, cranks for the pistons which are angularly displaced relative to each other by an angle other than 180 whereby upon forward operation the piston controlling the exhaust port leads the piston control ing the inlet port, an auxiliary exhaust port, a valve controlling the same, and means for opening said valve prior to the uncovering of the inlet port when the engine' is reversed.

In witness whereof, I have hereunto set my hand this 20th day of June, 1914.

OSKAR LASCHE.

Witnesses:

ERICH aanua, GUs'rAv HULBnocx. 

